<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        var num1 = parseFloat(prompt("请输入第一个数"))
        var num2 =  parseFloat(prompt("请输入第二个数"))
        var type = prompt("请输入运算类型")
        var result
        if (type == "+") {
            result = num1 + num2;
        }
        else if (type == "-") {
            result = num1 - num2;
        }
        else if (type == "*") {
            result = num1 * num2;
        }
        else if (type == "/") {
            if (num2 == 0) {
                alert("被除数不能为0")
            }
            else {
                result = num1 / num2;
            }
        }
        else if (type == "%") {
            result = num1 % num2;
        }
        alert(num1 + type + num2 + "的结果为" + result)
    </script>
</body>

</html>